Effect of Avermectin and Tetracycline on the Microbiome and Resistome of Beef Cattle
Project Title
Effect of Avermectin and Tetracycline on the Microbiome and Resistome of Beef Cattle
Researchers
Tim McAllister and Rahat Zaheer (AAFC Lethbridge)
| Status | Project Code |
|---|---|
| In progress. Results expected in December, 2022 | ANH.04.21 |
Background
Feedlots commonly use in-feed macrolide and tetracycline antibiotics to control liver abscesses. It turns out that the avermectins used for parasite control are also in the macrolide family [ivermectin (Ivomec, Bimectin, Bovimectin, Ivermectin, Solmectin), doramectin (Dectomax), eprinomectin (Eprinex, Longrange), selamectin (pets), and moxidectin (was Cydectin)]. To this point, no one’s looked at whether avermectins contribute to macrolide antibiotic resistance.
Objectives
- Assess the effect of LongRange® eprinomectin and tetracycline separately and in combination, on rumen and fecal microbiota and AMR and investigate cross-resistance and co-selection of AMR genes in the bacterial population.
What they will do
This team has already collected 200 rumen and 200 fecal samples through another project to assess the effect of LongRange® eprinomectin and tetracycline on the rumen microbiome, dung-feeding insects and the soil microbiome. In this trial they will use a subset of the rumen and fecal samples (50 each) from control and treated animals to characterize the microbiota and resistome using metagenomic sequencing.
Implications
This research will help assess whether the use of common parasite treatments may increase the risk of macrolide antibiotic resistance.